#include <iostream>
#include <string>
#include <cmath>

using namespace std;

int main() {
    auto func = [](uint64_t n){
        string s {to_string(n)};
        if (s.size() != 19)
            return false;
        string t {"1-2-3-4-5-6-7-8-9-0"};
        for (int i = 0; i < 20; i += 2) {
            if (s[i] != t[i])
                return false;
        }
        return true;
    };
    uint64_t ceiling = 1929394959697989990;
    uint64_t floor   = 1020304050607080900;
    for (uint64_t i = (static_cast<int>(sqrt(floor)) / 10) * 10; ; i += 10) {
        if (func(i * i)) {
            cout << i << ": " << i * i << endl;
            break;
        }
    }
}